Cat 235 remote field work

[brg]

brg
i need to build a portable boring machine, to sleeve two 3 1/2" x 20" pin holes in an excavator which are worn tapered up 5" any help appreciated.

[Jon]

Hi brg - welcome to HomemadeTools.net

Interesting! I'm going to see if any of our heavy equipment or machining folks have some ideas for you.

[drhall223]

brg
i need to build a portable boring machine, to sleeve two 3 1/2" x 20" pin holes in an excavator which are worn tapered up 5" any help appreciated.

I think the first issue is how to attach the boring head to the equipment. Once a mount is fabricated that will be rigid then mounting one of the high torgue, low speed portable drills could be doable. One of the larger 1hp model might work.

[mrehmus]

Take a look at those portable cylinder boring tools. They are designed to swing a single cutter through the bore. There are also welders to bring the bore back to size so you can remachine them to final size.

[mrehmus]

By the way, there are machine shops that specialize in on-site heavy machinery work.

[Hans Pearson]

Use a drill with a magnetic base as a milling machine with suitable supports for a boring bar.

[bvd1940]

My son has done this for a living and there is not much to it if you want to do it farmer style, you jut make an of set carriers on each side to hold your boring bar made out of a hefty piece of shafting which can use metal to metal close bored holes with plenty of lube.
The drive can be just about anything that can be speed controlled ie: gear mtr with chain and sprocket drive/large drill mtr.
When you finish one side flip boring bar around and repeat. you weld your offsets on to the equipment how ever you can get a good purchase on your equipment.
You will weld your sleeves once you get done with a pin to hold them straight while welding, should not take but a light ream to finish up the holes.
Good luck just remember its not as hard as it looks and keep it simple.
Bill

[ChrisB257]

My machining is rather small scale but - this sounds like a line boring operation. On YouTube CompedgeX described a very similar situation - his channel is here - https://www.youtube.com/channel/UCXi...nuVatgepDzydbw
The relevant video is this one -

Hope this might give some ideas.

[mrehmus]

Use a drill with a magnetic base as a milling machine with suitable supports for a boring bar.

The magnetic drills are only good for 1/2" or so. Not as big as he needs and they turn too fast for this job.

[jhovel]

Use a drill with a magnetic base as a milling machine with suitable supports for a boring bar.

That would be my advice too - in the absence of dedicated equipment like was shown in the video above. Flanged, self-aligning ball bearings bolted to a sacrificial flat steel bar and welded to the cat will work well to hold the DIY boring bar. Good luck and show us the results!